Synthesis and reaction kinetics of Pd(1,5-cyclooctadiene)Cl2 with N,N′-methylene-bis(2-aminopyridyl): An efficient catalyst for Suzuki-cross-coupling reactions

摘要: Abstract An inexpensive bidentate ligand N,N′-methylene-bis(2-aminopyridyl) (1) has been synthesized. Reaction of 1 with [Pd(COD)Cl2] affords a stable chelate complex, [{NC5H4N(H)(μ-CH2)(H)NC5H4N-κN,κN}PdCl2] (2). The kinetics the pseudo-unimolecular reaction Pd(1,5-cyclooctadiene)Cl2 studied over range 3.0 ⩽ 103 [1] ⩽ 7.0 mol dm−3, 30 °C ⩽ t ⩽ 40 °C. rate constants and equilibrium were calculated. Entropy enthalpy are found to be −42 ± 1 J K−1 mol−1 75 ± 1 kJ mol−1, respectively, which clearly indicates that substitution follows associative mechanism. complex 2 was tested for Suzuki-cross-coupling variety aryl halides boronic acids in methanol at room temperature or 60 °C, giving generally high yields both activated inactivated bromides. effect solvents as well base on Suzuki-coupling is also investigated.